Pneumonia (nu-MO-ne-ah) is an infection in one or both of the lungs. Many germs—such as bacteria, viruses, and fungi—can cause pneumonia.
The infection inflames your lungs' air sacs, which are called alveoli (al-VEE-uhl-eye). The air sacs may fill up with fluid or pus, causing symptoms such as a cough with phlegm (a slimy substance), fever, chills, and trouble breathing.
Pneumonia and its symptoms can vary from mild to severe. Many factors affect how serious pneumonia is, such as the type of germ causing the infection and your age and overall health.
Pneumonia tends to be more serious for:
Pneumonia is common in the United States. Treatment for pneumonia depends on its cause, how severe your symptoms are, and your age and overall health. Many people can be treated at home, often with oral antibiotics.
Children usually start to feel better in 1 to 2 days. For adults, it usually takes 2 to 3 days. Anyone who has worsening symptoms should see a doctor.
People who have severe symptoms or underlying health problems may need treatment in a hospital. It may take 3 weeks or more before they can go back to their normal routines.
Fatigue (tiredness) from pneumonia can last for a month or more.
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. To find clinical trials that are currently underway for Pneumonia, visit www.clinicaltrials.gov.
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